Blockout device

ABSTRACT

A blockout device for at least partially blocking a through cavity of a concrete block and supporting a settable material comprises a frangible region adapted to accommodate conduits of various transverse sizes, by providing an opening the size of which can be adjusted to accommodate a conduit of any of a number of different transverse sizes.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of foreign priority to Australiancomplete standard patent application No. 2011203311, filed on Jul. 6,2011, entitled BLOCKOUT DEVICE, which claims priority to Australianprovisional application no. 2010902992 filed on Jul. 6, 2010, entitledBLOCKOUT DEVICE, each of which are incorporated herein by reference.

FIELD

The present disclosure relates to a blockout device, and especially to ablackout devices for blocking a through cavity in a masonry block.

BACKGROUND

Hollow masonry blocks can be used to construct walls. The blocks may beprovided with a through cavity which in use extends between an openbottom of the block and an open top of the block. In a wall, blocks maybe arranged so that the cavities of vertically adjacent blocks arealigned to form a vertically extending cavity. One or more suchvertically extending cavities may be filled with a settable reinforcingmaterial, such as concrete, to provide a vertical reinforcement, orpillar, to enhance the strength of the wall. A wall may have a number ofsuch vertical reinforcements, spaced apart along the length of the wall.The spacing between such vertical reinforcements may be approximatelyone to two metres. It is normally not desired to provide more closelyspaced vertical reinforcements, due to the increased cost of doing soand, in particular, it is normally not desired to fill all of thevertically extending cavities with settable material. Thus only selectedblocks are filled with settable material.

To further strengthen the wall, a substantially horizontal reinforcingbeam (or “bond beam”) may be created. One way of creating such asubstantially horizontal beam is to provide steel reinforcing bars whichconnect a number of blocks at substantially the same height, and then topour a settable material such as concrete, to embed and secure thereinforcing bars and to fill the cavities in those blocks connected bythe reinforcing bars.

In such an exercise it is desirable to prevent the settable materialfrom flowing from the blocks to be filled into lower blocks (except,perhaps, for those selected blocks which are to form part of a verticalreinforcement, or pillar). A further consideration is that it may bedesirable to provide service conduits extending into, through, and outof, one or more of the vertically extending cavities.

One previous approach has been to provide metal block out plates torestrain the settable material from flowing from the blocks to be filledinto lower blocks. A known block out plate is described in AustralianPatent No. 568948. The block out plate described in this documentcomprises a planar body adapted to be wedged in a through cavity of amasonry block, just above the base of the block (i.e. at the bottom ofthe cavity), to block off the base of the block and prevent or reduceflow of concrete out of the base of the block. The described block outplate provides one or more indented portions which can be removed toprovide an aperture in the planar body to allow passage of a serviceconduit therethrough.

The inventor has perceived that there is a need for an improved, or atleast alternative, block out device.

SUMMARY

According to a first aspect of the present disclosure, there is provideda blockout device, for use with a masonry block having at least onethrough cavity, the blockout device comprising:

at least one blocking region, adapted to extend at least partiallyacross a through cavity of the masonry block in use, to at leastpartially block the through cavity, and to support a settable materialabove the block;

the at least one blocking region having a frangible region adapted toaccommodate conduits of various transverse sizes, by providing anopening the size of which can be adjusted to accommodate a conduit ofany of a number of different transverse sizes.

In an embodiment the opening may be formed by breaking or tearing one ormore parts of the frangible region.

In an embodiment the frangible region may be adapted to provide aplurality of openings, each for accommodating a conduit.

In an embodiment the size of the opening can be adjusted by breaking ortearing one or more parts of the frangible region.

In an embodiment the size of the opening can be adjusted by forcing theconduit through the frangible region.

In an embodiment the size of the opening is substantially determined bythe transverse size of the conduit forced therethrough.

In an embodiment the at least one blocking region is generally planar.

The frangible region may provide a number of predetermined areas ofweakness.

One or more of the areas of weakness may comprise a line of weakness.

The frangible region may provide an array of areas of weakness adapted,in use, to provide an aperture the size of which can be adjusted bybreaking, or tearing along, one or more of said areas of weakness.

One or more of said areas of weakness may comprise a line of weaknesssubstantially defining a circle. A plurality of lines of weakness may beprovided, forming substantially concentric circles.

The areas of weakness may be provided by perforations in the at leastone blocking region.

The frangible region may provide an array of perforations adapted, inuse, to provide an aperture the size of which can be adjusted bybreaking or tearing along appropriate lines of perforations.

The array of perforations may comprise one or more curved lines ofperforations.

One or more curved lines of perforations may define a circle.

The array of perforations may comprise one or more straight lines ofperforations.

The array of perforations may comprise a plurality of lines ofperforations which radiate outwardly relative to a common point, andwhich are angularly spaced apart about that common centre.

The frangible region may comprise an array of perforations adapted toallow an opening of any of a range of sizes to be formed.

The array of perforations may comprise a plurality of substantiallyconcentric circles of perforations.

The array of perforations may comprise more than one set ofsubstantially concentric circles of perforations.

One or more sets of substantially concentric circles of perforations maybe offset from the centre of the device.

The array of perforations may comprise a plurality of lines ofperforations which extend between two or more of the substantiallyconcentric circles of perforations.

The device may be generally rectangular.

The array of perforations may comprise one or more substantiallydiagonal lines of perforations.

The frangible region may be adapted to allow said conduit to passtherethrough, whilst accommodating said conduit sufficiently snugly tosubstantially prevent the passage of a settable material between theplanar region and the conduit.

In an embodiment the frangible region has a central portion which in usesubstantially corresponds to a transverse centre of a conduit whichpasses through the planar region, irrespective of the transverse size ofthe conduit.

In an embodiment the blockout device may be adapted to block out aplurality of masonry block through cavities. The blockout device maycomprise a plurality of frangible regions. The blockout device maycomprise two frangible regions. The blockout device may comprise fourfrangible regions. In use, each frangible region may be adapted tooverlie a corresponding masonry block through cavity. The device may beadapted to allow a first part of the device, provided with one or moreof said frangible regions, to be separated from a second part of thedevice. The second part of the device may be a part of the deviceprovided with one or more of said frangible regions.

According to a second aspect of the present disclosure there is provideda blockout device, for use with a masonry block having a through cavityin order to at least partially block one or more through cavities of themasonry block, the blackout device comprising:

at least one device support region adapted to be placed upon an uppersurface of a masonry block in order to support the blockout devicerelative to the upper surface;

at least one blocking region, the or each blocking region being for atleast partially blocking a through cavity of said masonry block and forsupporting settable building material; and

wherein at least one said blocking region is connected to at least oneintermediate region, the intermediate region being for supporting saidblocking region relative to at least one said device support region,wherein the intermediate region is adapted, in use, to extend downwardlyfrom the device support region and at least partially defines at leastone boundary of at least one device support region and/or at least oneblocking region.

In an embodiment at least one blocking region is adapted to provide, inuse, at least one aperture through which a conduit can pass from a firstside of the device to a second side of the device.

In an embodiment at least one blocking region is substantially planar.

In an embodiment at least one blocking region is adapted to supportsettable building material above the upper surface of said block.

In an embodiment one or more of said device support regionssubstantially define a periphery of the blockout device.

The or each device support region may be substantially planar.

All of the device support regions may be substantially coplanar.

The or each blocking region may be substantially planar.

The plane of at least one blocking region may be substantially parallelto the plane of at least one device support region.

The blocking region may be offset from the device support region in adirection corresponding to the direction perpendicular to the uppersurface of the block, in use.

One or more intermediate regions may define the perimeter of one of saidblocking regions.

One or more intermediate regions may be (but do not have to be)substantially perpendicular to the blocking region.

One or more intermediate regions may be angled at between 75 and 15degrees relative to the blocking region.

One or more intermediate regions may be angled at between 60 and 30degrees relative to the blocking region.

One or more intermediate regions may be (but do not have to be)substantially perpendicular to the at least one device support region.

One or more intermediate regions may be angled at between 75 and 15degrees relative to the at least one device support region.

One or more intermediate regions may be angled at between 60 and 30degrees relative to the at least one device support region.

In an embodiment one or more intermediate regions are adapted to extendfrom at least one device support region into a cavity of the block.

In an embodiment one or more intermediate regions are dimensioned andpositioned to assist in locating the device relative to a cavity of ablock.

In an embodiment the intermediate regions are dimensioned so that in usethey can assist in locating the device relative to a cavity, so that atleast one device support region of the device is located on an uppersurface of a block adjacent the cavity, so that the blocking region islocated just below the top of the cavity, and so that the intermediateregions extend into the cavity from the at least one device supportregion to the generally central region.

In an embodiment at least one said blocking portion, and its immediatelyadjacent intermediate region(s) have at least one overall dimensionwhich is substantially equal in size to a corresponding dimension of thecavity with which the device is to be used, thereby assisting inlocation of the device relative to the block.

In an embodiment at least one said blocking portion, and its immediatelyadjacent intermediate region(s) have at least one overall dimensionwhich is substantially equal in size to a corresponding dimension of thecavity of a standard size masonry block of a first standard size. Thestandard size masonry block of a first standard size may be masonryblock which is approximately 140 mm (plus or minus 20 mm) wide by 390 mm(plus or minus 20 mm) long. The standard size masonry block of a firststandard size may be a series 150 masonry block.

In an embodiment the periphery of the device may be dimensioned so thatthe device is adapted to be wedged into the cavity of a standard sizemasonry block of a second standard size. The periphery of the device maybe dimensioned so that the device is adapted to be wedged in a positionsuch that the device is oriented substantially parallel to the plane ofthe upper surface of the block. The standard size masonry block of asecond standard size may be masonry block which is approximately 190 mm(plus or minus 20 mm) wide by 390 mm (plus or minus 20 mm) long. Thestandard size masonry block of a first standard size may be a series 200masonry block.

In an embodiment the device is provided with a tab extending from a partthereof, to facilitate manual manipulation of the device.

In an embodiment the device is provided with a tab extending from anedge region thereof.

The tab may extend from a peripheral part of a device support region ofthe device.

In an embodiment the device is made from plastic.

In an embodiment the device is made from a single piece of plastic.

In an embodiment the device is made from a single piece of sheetplastic.

In an embodiment the blockout device is adapted to block out a singlethrough cavity of a masonry block.

In an embodiment the blockout device is adapted to block out a pluralityof masonry block through cavities. The blockout device may comprise aplurality of blocking regions. The blockout device may comprise twodiscrete blocking regions. The blockout device may comprise fourdiscrete blocking regions. In use, each blocking region is adapted to atleast partially block a corresponding masonry block through cavity. Thedevice may be adapted to allow a first part of the device, provided withone or more of said blocking regions to be separated from a second partof the device. The second part of the device may be a part of the deviceprovided with one or more of said blocking regions.

The blockout device in accordance with the second aspect may also be inaccordance with the first aspect. In this case, the (or each) frangibleregion may be provided as all or part of the (or a corresponding)blocking region.

According to a third aspect of the present disclosure there is provideda blockout device, for use with a masonry block having a through cavity,the blockout device comprising a blocking region, for at least partiallyblocking a through cavity of said masonry block, which is adapted toprovide, in use, at least one aperture through which a conduit can passfrom a first side of the device to a second side of the device, whereinat least part of the blockout device is made from a substantiallytransparent plastic, such that visibility, from the first side ofdevice, of part of a conduit which is on the second side of the device,is facilitated.

The first side of the device may correspond, in use, to an upper side ofthe device, and the second side of the device may correspond, in use, toa lower side of the device.

The device may further comprise one or more device support regionsadapted to be placed upon an upper surface of a masonry block in orderto support the blockout device relative to the upper surface.

The blocking region may be fabricated from a substantially transparentplastic.

The blockout device may be fabricated from a substantially transparentplastic.

The blockout device in accordance with the third aspect may comprise aplurality of blocking regions.

The blockout device in accordance with the third aspect may also be inaccordance with one or both of the first and second aspects.

According to a fourth aspect of the present disclosure there is provideda method of blocking a through cavity in a masonry block comprising useof a block out device in accordance with one or more of the first tothird aspects.

According to a fifth aspect of the present disclosure there is provideda method of blocking a through cavity in a masonry block, comprising:

placing a blockout device on the masonry block so that:

-   -   a peripheral region of the blockout device is supported by an        upper surface of the masonry block;    -   at least part of the device projects from the peripheral region        into the cavity; and    -   at least part of the device extends across the cavity so as to        be able to support a settable material above the block.

According to a further aspect of the present disclosure there isprovided a blockout device, comprising:

-   -   a peripheral region of the blockout device adapted to be        supported by an upper surface of a masonry block;    -   a projecting part of the device adapted to project from the        peripheral region into a cavity of the masonry block; and    -   a blocking part of the device adapted to extend at least        partially across the cavity so as to be able to support a        settable material above the block.

Features mentioned or set out above in relation to any one of the aboveaspects may applicable to one or more of the other aspects, and may beincorporated in embodiments in accordance with one or more of the otheraspects.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will now be described, by way of example only, withreference to the accompanying drawings in which:

FIG. 1( a) is a plan view of a embodiment of a blockout device inaccordance with the present disclosure;

FIG. 1( b) is a reproduction of FIG. 1( a) annotated with variousdimensions of a specifically sized embodiment.

FIG. 2 is an end view of the embodiment of FIG. 1( a);

FIG. 3 is a side view of the embodiment of FIG. 1( a);

FIG. 4 is a cross section on A-A of FIG. 1( a);

FIG. 5 is a perspective view of the embodiment of FIG. 1( a);

FIG. 6 is a perspective view corresponding to FIG. 5, but showing aconduit extending through the blockout device;

FIG. 7 is a schematic plan view showing the embodiment of FIGS. 1 to 5in use, blocking an upper region of a cavity of a masonry block.

FIG. 8( a) is a schematic cross sectional view on D-D of FIG. 7, alsoillustrating, in schematic cross section adjacent parts of a masonryblock wall in which the masonry block of FIG. 7 might be included inuse;

FIG. 8( b) is a reduced-scale representation corresponding to FIG. 8( a)also illustrating still more adjacent parts of a masonry block wall inwhich the masonry block of FIG. 7 might be included in use;

FIG. 9( a) is a plan view of a variation of the embodiment of FIGS. 1 to8( b) in which an alternative arrangement of perforations is used;

FIG. 9( b) is a reproduction of FIG. 1( a) annotated with an example ofdetails of the angular spacing between various lines of perforations;

FIG. 10( a) is a plan view of an alternative embodiment of a blockoutdevice in accordance with the present disclosure, which has differentdimensions to the embodiment of FIGS. 1 to 8( b), and is adapted for usewith a differently dimensioned masonry block;

FIG. 10( b) is a reproduction of FIG. 10( a) annotated with variousillustrative dimensions;

FIG. 11 is an end view of the embodiment of FIG. 10( a);

FIG. 12 is a side view of the embodiment of FIG. 10( a);

FIG. 13 is a cross section on B-B of FIG. 10( a);

FIG. 14 is a perspective view of the embodiment of FIG. 10( a);

FIG. 15 is a perspective view corresponding to FIG. 14, but showing aconduit extending through the blockout device;

FIG. 16 is a schematic plan view showing the embodiment of FIGS. 10( a)to 14 in use, blocking an upper region of a cavity of a masonry block;

FIG. 17 is a schematic cross sectional view on C-C of FIG. 16,additionally also illustrating, in schematic cross section, adjacentparts of a masonry block wall in which the masonry block of FIG. 7 mightbe included in use;

FIG. 18( a) is a plan view of a variation of the embodiment of FIGS. 10(a) to 17 in which an alternative arrangement of perforations is used;

FIG. 18( b) is a reproduction of FIG. 18( a) annotated with an exampleof details of the angular spacing between various lines of perforations;

FIG. 18( c) is a plan view of a further variation in which analternative arrangement of perforations is used;

FIG. 19 is a schematic plan view of an alternative embodiment, adaptedto block two cavities; and

FIG. 20 is a schematic plan view of a further alternative embodiment,adapted to block four cavities.

DETAILED DESCRIPTION OF EMBODIMENTS

With reference to FIGS. 1( a) to 6 an embodiment of a blockout device,generally designated 1, for use with a masonry block having a throughcavity, comprises a blocking region, which in this embodiment is in theform of a generally planar region 10, adapted to extend across most ofthe through cavity of the masonry block in use in order to at leastpartially block the cavity and to support a settable material above theblock. The generally planar region 10 is generally rectangular, andprovides a frangible region 20 through which a conduit can be forced.The frangible region 20 allows the device 1 to accommodate a conduit ofany of a range of transverse sizes. This is accomplished by thefrangible region being able to provide various sizes of opening forpassage of a conduit therethrough. In this embodiment the frangibleregion 20 can be broken, to provide an aperture of appropriate size fora given conduit, by forcing the given conduit through the frangibleregion. More specifically, the frangible region 20 provides an array ofperforations which together, in use, provide an aperture the size ofwhich can be adjusted by breaking or tearing along appropriate lines ofperforations. In the illustrated embodiment of a blockout device 1 thearray of perforations includes curved lines of perforations (whichdefine circles, as will be described below) and may include straightlines of perforations to facilitate breaking or tearing. Thus the sizeof the aperture created can be substantially determined by thetransverse size of the conduit forced therethrough. In the illustratedembodiment the blockout device 1 is made of a suitable plastic, having athickness of approximately 1 mm (although a lesser thickness may besuitable, depending on the plastic used and strength required).

In this embodiment the frangible region comprises an array ofperforations in the form of a plurality of substantially concentriccircles of perforations. More specifically, in this embodiment the arrayof perforations comprises first to fourth concentric circles ofperforations 21, 22, 23, 24. The frangible region is provided with acentral aperture 25. In this embodiment the first to fourth concentriccircles of perforations 21, 22, 23, 24 have diameters of 45 mm, 35 mm,25 mm and 10 mm respectively, and the central aperture 25 has a diameterof 5 mm. The array of perforations further comprises first to fourthlines of perforations 26, 27, 28, 29 each of which extends from thesmallest, innermost, circle of perforations 24, substantially to corners31, 32, 33, 34 of the rectangular generally planar region 10. Thus thelines of perforations 26, 27, 28, 29 extend or radiate outwardly from anapproximate centre of the frangible region. Of course it will beappreciated that alternative arrangements of perforations are possible(for example more or fewer circles and/or radiating lies could be used,the circles of perforations could be joined by staggered lines segmentsof perforations, instead of the continuous lines of perforations 26, 27,28, 29, etc.)

The frangible region 20 is thus adapted to allow a conduit of any of arange of sizes to pass therethrough, whilst accommodating the conduitsufficiently snugly to substantially prevent the passage of a settablematerial between the planar region 10 and the conduit. For example, if aconduit with an outside diameter of 25 mm were to be used, the frangibleregion could be broken along the third circle of perforations 23 (forexample by pushing the conduit through the frangible region so as totear the frangible region along the third circle of perforations 23) andthe conduit could then be passed through the resulting 25 mm diameteraperture, with the boundary of that aperture fitting sufficientlyclosely to the exterior of the conduit to prevent substantial leakage ofa settable material (which, in this application is typically quiteviscous and is normally concrete) between the device 1 and the conduit.FIG. 6 illustrates a conduit 35 (which as illustrated has an externaldiameter of approximately 25 mm) extending though an aperture formed bybreaking or tearing the frangible region along the third circle ofperforations 23.

It should be appreciated that if a conduit with an outside diameter of23 mm or 24 mm were used, any small gap between a 25 mm diameteraperture and the outside wall of the conduit would be sufficiently smallto avoid problematic leakage of settable material between the device 1and the conduit. Similarly, the generally planar region may, in use beadapted to fit other sizes of conduit by breaking or tearing appropriateparts of the frangible region, preferably utilising the perforations.

Because the circles of perforations are, in this embodiment, concentric,with their centres corresponding to the centre of the device, a circularconduit will, in use, be located substantially concentric with theperforated circles, and this at the centre of the device 1.

In use, the generally planar region 10 is adapted to be located justbelow the top surface of a masonry block, and just inside a throughcavity of the masonry block, so as to support settable material abovethe block.

The blockout device 1 further comprises at least one support region,which in this embodiment is in the form of a peripheral rim 40, adaptedto be placed upon an upper surface of the masonry block in order tosupport the blockout device relative to the upper surface. The generallyplanar region 10 is provided at a generally central region of the device1 and is surrounded by the peripheral rim 40. The blockout device 1further comprises an intermediate region, which in use extends in adirection perpendicular to the upper surface of the block, and whichdefines and connects the inner boundary of the peripheral rim 40 and theouter boundary of the generally planar region. In this embodiment theintermediate region is provided by an inclined region 50, angled atapproximately 45 degrees to the peripheral rim 40, surrounding therectangular planar region 10 and having first and second longer sides51, 52, first and second shorter sides 53, 54 and first to fourthsomewhat rounded corner regions 55, 56, 57, 58. The inclined region 50thus spaces apart and offsets the generally planar region 10 from theperipheral rim 40, in this embodiment by approximately 5 mm to 6 mm, ina direction perpendicular to the upper surface of the block. Thus whenthe peripheral rim 40 rests on the upper surface of a masonry block, thegenerally planar region 10 is located just below the top surface, andjust inside the through cavity, of the masonry block.

In the illustrated embodiment 1 the peripheral rim 40 forms a generallyrectangular border of the device 1, is generally planar, and comprisesfirst and second longer sides 41, 42, first and second shorter sides 43,44 and first to fourth somewhat rounded corners 45, 46, 47, 48. Anelongate tab 49 projects outwardly from the peripheral rim 40, and mayassist in manual manipulation of the device. For example, the tab 49 maybe used to manually retrieve the device if it inadvertently becomesinserted in the cavity of a block.

With reference to FIG. 7, the blockout device 1 is particularly adaptedfor use with a masonry block 60 (shown in plan view from above in FIG.7) which has two substantially rectangular through cavities 61, 62extending from the top surface 63 to the bottom surface (not shown)thereof. The masonry block 60 is generally rectangular and may beregarded as having first and second, longer, side walls 64, 65, firstand second, shorter, laterally extending end walls 66, 67, and anlaterally extending intermediate wall 68 which is generallyperpendicular to the side walls 64, 65, generally parallel to the endwalls 66, 67, and extends between central portions of the side walls 64,65. Thus the first through cavity 61 may be regarded as being definedby: the first end wall 66; first-end parts of the first and second sidewalls 64, 65; and a first-end side of the intermediate wall 68.Similarly, the second through cavity 62 may be regarded as being definedby: the second end wall 67; second-end parts of the first and secondside walls 64, 65; and a second-end side of the intermediate wall 68.Such masonry blocks are provided commercially in any of a small numberof different standard sizes. The blockout device 1, in this particularembodiment, is dimensioned specifically for use with a standard sizeblock, sometimes called a series 150 block, and the width of the partswhich are adapted to extend into the cavity 62 (ie width of thegenerally planar region 10 plus the inclined region 50) is approximately60 mm, which is only very slightly less than the width of the cavity 62of a series 150 block. The blockout device 1 has an overall length(excluding the tab) of approximately 140 mm, an overall width ofapproximately 115 mm. These dimension allow the device 1 to be forcedinto, and be retained within the cavity of larger standard size block (aseries 200 block), in order to support a settable material, thusproviding a useful secondary functionality for this embodiment 1, whichwill be described further in due course. Of course a blockout devicehaving features similar to this embodiment 1 could have differentoverall dimensions and need not have the secondary functionality.

Thus the width and length of the device 1 are sufficient to block outone of the cavities (the second cavity, 62, as illustrated in FIG. 7).The width and length of the peripheral rim 40 are greater than therespective width and length of each of the cavities 61, 62, so that inuse at least a peripherally outermost part of the peripheral rim 40 canrest upon the top surface of the block which surrounds the cavity 62which is to be blocked out. The overall lateral width of the peripheralrim 40 is less than the width of the block 60, and more specificallyless than the width of the top surface 63 of the block 60, so that partsof the top surface of the block extend laterally beyond device 1. Thewidth of the parts of the device 1 which are, in use, vertically offsetfrom the peripheral rim 40 (i.e. the combined width of the planar region10 and the inclined region 50) is only slightly less than the width ofthe cavity 62. Thus placing the device 1 on the block so that the planarregion 10 is in the cavity, below the top surface 63 of the block 60,effectively locates the device laterally relative to the block 60. Thedevice 1 can thus easily be placed in a position in which the peripheralrim 40 rests on the top surface 63 of the block, and in which the deviceis positioned to block out a cavity of the block (cavity 62, asillustrated in FIG. 7). The device 1 can then be secured in position byplacing mortar on the peripheral rim 40 and on the adjacent top surface63 of the block 60, so that the device 1 is held in position, relativeto the block 60, by the mortar. More specifically, the device 1 can besecured in position by placing mortar on the longer sides 41, 42 of theperipheral rim 40, and on the adjacent top surface 63 of the block 60,so that mortar overlies and bridges the periphery of the device 1, andholds the device 1 is position, relative to the block 60. Of course,other methods of securing the device relative to the block could be used(for example, but not limited to, use of a thin layer of a suitableadhesive between the device and the block).

The peripheral rim 40 may be provided with one or more characteristicsor features which facilitate securing of the device 1 to the block 60.In an embodiment, such characteristics or features comprise featureswhich facilitate securing of the device 1 by mortar by enhancing secureengagement of the peripheral rim 40 by mortar, once the mortar is set.For example, rather than providing a smooth upper surface, theperipheral rim may be provided with texturing, apertures, slots and/orprotuberances so that the peripheral rim 40, and thus the device, can beheld securely by set mortar laid across the top of the rim 40 and block60. In one embodiment, the peripheral rim is provided with one or moreupwardly projecting protuberances formed by one or more correspondingregions of increased thickness, for example, as illustrated in FIG. 18(c) which will be described in detail below, an upwardly projecting ridge348 is provided. (In the particular embodiment illustrated in FIG. 18(c) the upwardly projecting ridge extends upwardly approximately 1 mm(0.04 inches) and extends around the device, just within the outerperiphery of the peripheral rim, although it will be appreciated thatthis is just one example of a feature which facilitates entrapment ofpart of the peripheral rim by set mortar, and any suitably configuredfeature could be used.) Having the peripheral rim 40 securely locatedrelative to the block 60 may be useful, depending on the stiffness ofthe device and the load/pressure of settable material to be borne, inavoiding downwards bowing and collapse of the device under the load ofthe settable material which could occur under some circumstances if theperipheral rim 40 were not adequately secured and were thus able to bepulled into the cavity by the load of settable material.

FIG. 8( a) shows, in schematic cross section, part of a masonry blockwall, and illustrates the blockout device 1 in use, in a positionrelative to the block 60 corresponding to that illustrated in FIG. 7.The blockout device 1 extends slightly into the cavity 62 of block 60and supports a settable filling material above the block, for example sothat the material can form part of a horizontally extending beam 69A. Byway of illustration a first additional block 60A, having cavities 61A,62A, and a second additional block 60B, having cavities 61B, 62B areillustrated. The first additional block 60A is located (in the courseabove the block 60) so that the first cavity 61A thereof is directlyabove the device 1 and directly above the second cavity 62 of the block60. The second additional block 60B is located horizontally adjacent theblock 60, so that the first cavity 61B thereof is directly below thesecond cavity 62A of the first additional block 60A.

The settable filling material is used to fill the cavities 61A, 62A ofthe first additional block 60A, for example to provide part 69A of ahorizontally extending beam. The device 1 supports the settable fillingmaterial in the first cavity 61A of the first additional block 60A abovethe block 60, and prevents it falling into the blocked out second cavity62 of the block 60. Conduit 35 (placed prior to provision of thesettable filling material) extends though the device 1 to provideservice distribution in the finished construction. The first cavity 61Bof the second additional block 60B is not provided with a blockoutdevice, and settable filling material has therefore fallen from thesecond cavity 62A of the first additional block 60A into the firstcavity 61B of the second additional block 60B. It may be desirable toallow such downwards passage of settable filing material at selectedlocations in order to provide one or more pillars 69B.

FIG. 8( b) illustrates schematically a larger section of masonry blockwall, which additionally includes third, fourth, fifth and sixthadditional blocks 60C, 60D, 60E, 60F. As illustrated, blockout devices 1are used with all the blocks which are in the same course as block 60,in order to support settable filling material thereabove, for example tofor a horizontally extending beam 69C. More specifically, blockoutdevices 1 are used with: first and second cavities 61, 62 of block 60,second cavity 62B of second additional block 60B, and first and secondcavities 61D, 62D of fourth additional block 60D. The first cavity 61Bof the second additional block 60B is not provided with a blockoutdevice, as set out above, in order to allow formation of pillar 69B. Asillustrated schematically in FIG. 8( b) the horizontal beam 69C andpillar 69B may be provided with reinforcing bars 70, 71. The blocks inthe course above the block out devices 1 may of the type known as ‘knockout bond beam’ blocks, which are provided with slots or apertures intheir laterally extending walls to facilitate accommodation of one ormore generally horizontally extending reinforcing bars 70.

It will be appreciated that in constructing a masonry block wall or wallsection, as illustrated schematically in FIGS. 8( a) and 8(b),embodiments of the blockout device disclosed herein can easily bepositioned as desired, on the upper surfaces of selected masonry blocks.If repositioning or removal of one or more blockout devices is desired,this can easily be achieved prior to the devices being fixed in place(eg by use of mortar). If a device 1 is fixed in place, positioned toblock out a cavity which it is subsequently desired not to block out,unblocking of the cavity is still relatively easy and convenient, sincethe blockout device 1, being made of a sheet plastic material, can becut, broken or melted, without undue difficulty, using equipment whichbuilders will typically have conveniently to hand. The disclosedembodiment is also light and large numbers are easy to transport andcarry. The plastic blockout devices 1 are also economical tomanufacture, and may have low environmental impact (eg carbon footprint)especially if made from a recycled plastic. Further, the perforatedregion facilitates provision of an aperture therethrough to accommodatea conduit of any of a range of sizes. The device can be made from atransparent plastic, which can assist in positioning a bottom part of aconduit, since it allows a user to see the part of the conduit which isbelow the device. The blockout devices can be manufactured by a suitableplastic thermoforming or plastic injection process.

At least some of these features are in marked contrast to features of atleast some known attempts at providing devices for blocking masonryblock cavities. One known device comprises a metal planar body or plateadapted to be wedged in a through cavity of a masonry block, just abovethe base of the block (i.e. at the bottom of the cavity), to block offthe base of the block and prevent or reduce flow of concrete out of thebase of the block. The planar body provides several separate, spacedapart, circular indented portions of different diameters, a selected oneof which can be pushed out from its location on the plate leave asuitably sized aperture in the planar body to allow passage of a serviceconduit therethrough. Once wedged into a cavity, such devices can bevery difficult to remove. Further, because the parts which can provideapertures are indented metal portions, connected by metal parts to theremainder of the planar body, they can be difficult to remove, andprovision of an aperture for a conduit can be difficult. This isespecially true if the device has been wedged into a cavity with thewrong side of the device facing upwards, since the indented portions aredifficult or impossible to push out from the ‘wrong’ side of the plate.The above described difficulty in removing the wedged planar body fromthe bottom part of a masonry block exacerbates this problem, since theincorrectly oriented planar body cannot easily be removed and replacedin the correct orientation. Manufacture from metal plate makes someknown devices relatively heavy (and therefore less convenient to carryin large numbers), and also relatively expensive to manufacture andrelatively environmentally unfriendly. Metal plates are also opaque, sothat visibility of part of a conduit which is below the plate is poor ornon-existent.

Of course, it should be appreciated that many variations of thedescribed embodiment 1 of a blockout device are possible. For exampleFIGS. 9( a) and 9(b) illustrate an embodiment 100 which is, in many wayssimilar to the embodiment 1 illustrated in FIGS. 1 to 7, differing onlyin that it has an alternative arrangement of perforations. In thisembodiment 100 the frangible region 120 comprises an array ofperforations in the form of a number of lines radiating away from, andangularly space about, a single circle of perforations. Morespecifically, in this embodiment the array of perforations comprises asingle circle of perforations 121 and first to twelfth lines 122 to 133,angularly spaced apart by approximately between about 27 degrees andabout 35 degrees, and radiating outwardly (towards intermediate portion150) from the single circle of perforations 121. In use this provides agenerally triangular segment of generally planar region 110 between eachtwo neighbouring lines of perforations. Forcing a conduit through thefrangible region 121 has the effect of tearing along the lines ofperforations sufficiently to form an aperture (by separation anddeformation of the generally triangular segments) just large enough toaccommodate the conduit.

FIGS. 10( a), 10(b), 11, 12, 13, 14, 15, 16 and 17 show an alternativeembodiment 200 which, it will be appreciated, has many similarities inprinciple and design to the blockout device 1, but which is a largerdevice suitable for use with a larger masonry block. The embodiment 200is suitable for use with a 190 mm wide by 390 mm long masonry block(sometimes called a “series 200” masonry block, although series 200blocks may have slightly differing sizes) in contrast to the device 1which is suitable for use with a 140 mm wide by 390 mm long masonryblock (sometimes called a “series 150” masonry block, although series150 blocks may have slightly differing sizes). It will be appreciatedthat there are many similarities between the blockout device 200 and theblockout device 1, and the similarities will not be described in detailherein. It will further be appreciated that FIGS. 10( a), 10(b), 11, 12,13, 14, 15, 16 and 17, respectively correspond in general terms to theviews of FIGS. 1( a), 1(b), 2, 3, 4, 5, 6, 7 and 8(a) respectively, butillustrate the larger embodiment 200. The blockout device 200 isdimensioned specifically for use with series 200 blocks, and has anoverall length (excluding the tab) of approximately 160 mm, and anoverall width of approximately 140 mm. The width of the parts which areadapted to extend into a cavity of a masonry block (ie width ofgenerally planar region 210 plus inclined region 250) is approximately100 mm, which is only slightly less than the width of the cavity in theseries 200 block. In a 190 mm wide by 390 mm long “series 200” masonryblock the width of the cavity is approximately 110 mm, and the length ofthe cavity is approximately 135 mm: thus it will be appreciated that thesmaller embodiment 1 (of FIGS. 1( a), 1(b), 2, 3, 4, 5, 6, 7 and 8(a))is dimensioned so that can be forced into the cavity of a series 200block, in order to support a settable material, as foreshadowed above.

As the width of generally planar region 210 of device 200 isconsiderably greater than the width of the generally planar region 10 ofdevice 1, a greater number of concentric circles of perforations can beprovided (allowing effective accommodation of a greater range of conduitsizes). As illustrated, device 200 includes eight concentric circles 224of perforations (although, of course, other numbers could be provided ifdesired).

FIG. 15 illustrates the blockout device 200 with a 25 mm outsidediameter conduit 35 extending therethrough.

FIG. 16 illustrates the blockout device 200 positioned, for use, on aseries 200 block 260.

FIG. 17 illustrates the blockout device 200 positioned in part of a wallstructure.

As with the smaller embodiment, alternative embodiments are of coursepossible, and FIGS. 18( a) and 18(b) illustrate an embodiment of ablockout device 300, which has many similarities to the blockout device200, but adopts an alternative array of perforations, configured withsimilarities to the array of perforations in the embodiment 100 of FIGS.9( a) and 9(b). In this embodiment 300 frangible region 320 comprises anarray of perforations in the form of a number of lines radiating awayfrom, and angularly spaced about, a single circle of perforations. Morespecifically, in this embodiment the array of perforations comprises asingle circle of perforations 321 and first to sixteenth lines (eg line322) angularly spaced apart by approximately between about 20 degreesand about 25 degrees, and radiating outwardly (towards intermediateportion 350) from the single circle of perforations 321. In use thisprovides a generally triangular segment of generally planar region 310between each two neighbouring lines of perforations. It will beappreciated that, as illustrated, the greater angular spacings arebetween adjacent lines which are orientated in or close to the width orlateral direction of the blockout device (ie shorter lines) and thelesser angular spacings are between adjacent lines which are orientatedin or close to the length direction of the blockout device (ie longerlines), which avoids undue disparity in the size and area of thetriangular segments. Forcing a conduit through the frangible region 321has the effect of tearing along the lines of perforations sufficientlyto form an aperture (by separation and deformation of the generallytriangular segments) just large enough to accommodate the conduit.

FIG. 18( c) illustrates a further alternative embodiment of a blockoutdevice 360, which has many similarities to the previously describedembodiments, but which provides an alternative array of perforations. Inthis embodiment 360 frangible region 362 comprises an array ofperforations having similarities to the array of perforations in theblockout device 1, but further including a number of apertures 364, andconcentric circles of perforations 366 which are offset from the centerof the device. This provides additional utility in enabling the blockoutdevice 360 to accommodate more than one conduit and/or other elongatemembers. Further, there may be circumstances in which it is desired tohave a conduit or other elongate member offset from the centre of thecavity, and the blockout device 360 accommodates this. Morespecifically, in this embodiment, in addition to the aperture andperforations provided by the blockout device 1, the blockout device 360provides apertures 364 and concentric circles of perforations 366 whichare offset from the centre of the device towards corners of generallyrectangular generally planar region 368. In this embodiment four offsetgroups of perforations are provided, but it will be appreciated that, invariations, different numbers of offset groups could be provided. Itwill be appreciated that each group is similar in operation to the arrayprovided in the blockout device 1: for example, an opening can becreated (or enlarged) by forcing a conduit through a part of thefrangible region corresponding to a group, and the size of the openingcan be adjusted by selective breaking/tearing of the frangible region,and may be effectively determined by the transverse size of a conduitpushed through the frangible region. In a further variation, the offsetgroups do not include an aperture: in such a variation groups ofperforations, optionally laid out as concentric circles, but withoutrespective apertures associated therewith may be provided. In furthervariations different parts of the frangible region, each adapted toprovide an opening might not overlap (or intersect) as is the case inthe blockout device 360.

In the illustrated embodiments the frangible regions are provided bymeans of perforations. In some embodiments the perforations comprisesmall holes or apertures which are elongate in the direction of thelines formed by the perforations, adjacent perforations are separated bybridges of plastic, and each perforation (aperture) has a length betweentwo and four times the length of the bridge (although it is notessential that all the apertures, or all the bridges are of equaldimensions). Such an arrangement has been found to provide sufficientweakness to allow a conduit to be forced through the frangible area, butsufficient strength to adequately support settable material above thedevice, in use. However, the configuration may be varied if desired,according the strength and thickness of the material used, desiredstrength, and/or other factors.

Many further variations are possible. For example, other types offrangible areas or lines could be used. For example the frangible regioncould be provided by one or more areas or lines of weakness comprisingone or more areas of reduced thickness (rather than through apertures).Such lines of weakness could have ‘bridges’ of greater thicknesstherebetween (similar to bridges in the lines of apertures describedabove), but provision of such bridges might not be necessary, dependingon the material and requirements for the device.

Furthermore a blockout device could comprise two or more areas, eachadapted to block a through cavity, so that the device is essentiallyequivalent to two or more block out devices, as described above, formedas a single device. FIG. 19, for example, illustrates schematically anembodiment 400, of a blockout device, which comprises first and secondblocking regions (which may additionally or alternatively comprisefrangible regions) 410, 420 respectively, each adapted to be locatedjust inside a cavity 61, 62 of a masonry block (eg, block 60, which isshown in FIG. 19 to illustrate the relative dimensions of the embodiment400 and a masonry block 60 with which the embodiment 400 is intended foruse). It will be appreciated that the embodiment 400 effectivelycomprises two of the blockout devices 1, of FIGS. 1( a), 1(b), 2, 3, 4,5, 6, 7 and 8(a), formed as a single unit, and that similarities betweenthe embodiments will not be described explicitly. However, it will beappreciated that a device support region 440 located between the firstand second blocking regions 410, 420, is dimensioned so that the firstand second blocking regions 410, 420 can each be located just inside acavity of a masonry block (eg, block 60), in use. The embodiment 400 maybe advantageous over the embodiment blockout devices 1, since only onedevice per block, rather than two, need be used, which may enhanceconvenience and facilitate use.

FIG. 20 illustrates schematically a further embodiment 500, of ablockout device, which comprises first to fourth blocking regions (whichmay additionally or alternatively comprise frangible regions) 510, 515,520, 525 respectively. Since this embodiment has four blocking regions,it will be appreciated that it is adapted to be used to block fourcavities: eg, the cavities of two adjacent blocks. Thus, as illustratedin FIG. 20, the first to fourth blocking (and/or frangible) regions 510,515, 520, 525 are each adapted to be located just inside a cavity 61,62, 61A, 62A of masonry blocks 60, 60A. It will be appreciated that theembodiment 500 effectively comprises four of the blockout devices 1, ofFIGS. 1( a), 1(b), 2, 3, 4, 5, 6, 7 and 8(a) formed as a single unit.However it will be appreciated that one or more device support regions530, 532, 536 located between neighbouring blocking regions 510, 515,520, 525 are dimensioned so that the blocking regions 510, 515, 520, 525can each be located just inside a cavity 61, 62, 61A, 62A of one of themasonry blocks 60, 60A, in use. The embodiment 500 may be advantageousover the embodiment blockout devices 1, since only one device per twoblocks need be used, which may enhance convenience and facilitate use.However, it will be appreciated that, in use, the number of cavities ina course of blockwork which requires blocking out will frequently not bea multiple of four. Thus, in order to facilitate use in suchcircumstances, the embodiment 500 is provided with division lines 540,542, 544, 546 (which may be lines of perforations) which allow theembodiment 500 to be divided into a number of parts. Each part may beequivalent to one, two or three of the blockout devices 1, of FIGS. 1(a), 1(b), 2, 3, 4, 5, 6, 7 and 8(a), and additionally, in thisembodiment, the embodiment 500 includes a spacing part 450 between thetwo pairs of blocking regions 510, 515, 520, 525. If desired, some oreach of the parts into which the embodiment 500 can be divided may bedimensioned so as to be able to fit within the cavity of a larger blockthan the block 60, 60A for which the embodiment is primarily intended,as discussed above with reference to the ‘secondary functionality’ forthe embodiment 1.

It is to be understood that, if any prior art publication is referred toherein, such reference does not constitute an admission that thepublication forms a part of the common general knowledge in the art, inAustralia or any other country.

It will be understood to persons skilled in the art of the inventionthat many modifications may be made without departing from the spiritand scope of the invention.

In the claims which follow and in the preceding description of theinvention, except where the context requires otherwise due to expresslanguage or necessary implication, the word “comprise” or variationssuch as “comprises” or “comprising” is used in an inclusive sense, i.e.to specify the presence of the stated features but not to preclude thepresence or addition of further features in various embodiments of theinvention.

1. A blockout device, for use with masonry blocks having at least onethrough cavity, the blockout device comprising: at least one blockingregion, adapted to extend at least partially across a through cavity ofthe masonry block in use, to at least partially block the throughcavity, and to support a settable material above the block; the at leastone blocking region having a frangible region adapted to accommodateconduits of various transverse sizes, by providing an opening the sizeof which can be adjusted to accommodate a conduit of any of a number ofdifferent transverse sizes.
 2. A blockout device as claimed in claim 1,wherein the size of the opening can be adjusted by breaking or tearingone or more parts of the frangible region.
 3. A blockout device asclaimed in claim 2, wherein the size of the opening can be adjusted byforcing said conduit through the frangible region, so that the size ofthe opening is substantially determined by the transverse size of theconduit forced therethrough.
 4. A blockout device as claimed in claim 3wherein the frangible region provides an array of areas of weaknessadapted, in use, to provide an aperture the size of which can beadjusted by breaking, or tearing along, one or more of said areas ofweakness.
 5. A blockout device as claimed in claim 3, wherein saidfrangible region comprises a plurality of lines of weakness provided inthe blocking region, forming at least one set of substantiallyconcentric circles.
 6. A blockout device as claimed in claim 3, whereinthe frangible region provides an array of perforations, the arraycomprising a plurality of lines of perforations, and the array beingadapted, in use, to provide an aperture the size of which can beadjusted by breaking or tearing along appropriate lines of perforations.7. A blockout device as claimed in claim 6, wherein the array ofperforations comprises one or both of: at least one curved line ofperforations defining a circle; and a plurality of lines of perforationswhich radiate outwardly relative to a common point and which areangularly spaced apart about that common point.
 8. A blockout device asclaimed in claim 7, wherein the array of perforations comprises at leasttwo sets of substantially concentric circles of perforations.
 9. Ablockout device as claimed in claim 8, wherein the array of perforationsfurther comprises a plurality of lines of perforations which extendbetween two or more substantially concentric circles of perforations.10. A blockout device as claimed in claim 3, wherein the frangibleregion is adapted to allow a conduit to pass therethrough, whilstaccommodating said conduit sufficiently snugly that in use passage of asettable construction material between the blocking region and theconduit is substantially prevented.
 11. A blockout device as claimed inclaim 1, wherein the blockout device is be adapted to block out aplurality of masonry block through cavities, and comprises a pluralityblocking regions adapted to block respective masonry block throughcavities, each blocking region being provided with a frangible region.12. A blockout device as claimed in claim 11, wherein the blockoutdevice is provided with a further frangible region adapted to allow afirst part of the device, provided with a blocking region, to beseparated from a second part of the device provided with a blockingregion.
 13. A blockout device as claimed in claim 1, further comprisingat least one device support region adapted to be placed upon an uppersurface of a masonry block in order to support the blockout devicerelative to the upper surface; wherein at least one said blocking regionis connected to at least one intermediate region, the intermediateregion being for supporting said blocking region relative to at leastone said device support region, wherein the intermediate region isadapted, in use, to extend downwardly from the device support region andat least partially defines at least one boundary of at least one devicesupport region and at least one blocking region.
 14. A blockout deviceas claimed in claim 3, wherein the frangible region is adapted toprovide a plurality of openings, each opening adapted to allow a conduitto pass therethrough, and wherein the frangible region is configured sothat the size of each opening is adjustable to accommodate a conduit ofany of a number of different transverse sizes.
 15. A blockout device asclaimed in claim 1, wherein at least part of the blockout device is madefrom a substantially transparent plastic, such that visibility, from afirst side of device, of part of a conduit which is on a second side ofthe device, is facilitated.
 16. A blockout device, for use with amasonry block having a through cavity in order to at least partiallyblock one or more through cavities of the masonry block, the blockoutdevice comprising: at least one device support region adapted to beplaced upon an upper surface of the masonry block in order to supportthe blockout device relative to the upper surface; at least one blockingregion, the or each blocking region being for at least partiallyblocking a through cavity of said masonry block and for supportingsettable building material; and wherein at least one said blockingregion is connected to at least one intermediate region, theintermediate region being for supporting said blocking region relativeto at least one said device support region, wherein the intermediateregion is adapted, in use, to extend downwardly from the device supportregion.
 17. A blockout device as claimed in claim 16, wherein at leastone blocking region is substantially planar, wherein the or each devicesupport region is substantially planar and wherein the plane of at leastone blocking region is substantially parallel to a plane of at least onedevice support region.
 18. A blockout device as claimed in claim 16,wherein one or more intermediate regions is angled at between 90 and 15degrees relative to the blocking region.
 19. A blockout device asclaimed in claim 16, wherein at least one blocking region is configuredto provide, in use, at least one aperture through which a conduit canpass from a first side of the device to a second side of the device. 20.A blockout device as claimed in claim 16, wherein one or moreintermediate regions are adapted to extend, in use, from at least onedevice support region supported on an upper surface of the block, into acavity of the block and to assist in locating the device relative to acavity of a block so that the blocking region is located in the cavityof the block below the top of the cavity, by engaging a part of theblock which defines the cavity thereof.
 21. A blockout device as claimedin claim 20, wherein at least one said blocking region, and itsimmediately adjacent intermediate region(s) have at least one overalldimension which is substantially equal in size to a correspondingdimension of the cavity of a masonry block of a standard size, therebyassisting in location of the device relative to the block.
 22. Ablockout device as claimed in claim 21, wherein the periphery of thedevice is dimensioned so that the device is adapted to be wedged intothe cavity of a standard size masonry block of a second standard sizesuch that the device is oriented substantially parallel to a planedefined by the upper surface of the block.
 23. A blockout device asclaimed in claim 16, wherein the device is made from a single piece ofplastic.
 24. A blockout device as claimed in claim 16, wherein theblackout device comprises a plurality of blocking regions and is adaptedto block out a plurality of masonry block through cavities.
 25. Ablockout device as claimed in claim 16, wherein the blockout devicecomprises two or more discrete blocking regions, each adapted to atleast partially block a corresponding masonry block through cavity. 26.A blockout device as claimed in claim 25, wherein the blockout device isprovided with a frangible region adapted to allow a first part of thedevice, provided with a blocking region, to be separated from a secondpart of the device provided with a blocking region.
 27. A blockoutdevice, for use with a masonry block having a through cavity, theblockout device comprising a blocking region, for at least partiallyblocking a through cavity of said masonry block, which is adapted toprovide, in use, at least one aperture through which a conduit can passfrom a first side of the device to a second side of the device, whereinat least part of the blockout device is made from a substantiallytransparent plastic, such that visibility, from the first side ofdevice, of part of a conduit which is on the second side of the device,is facilitated.
 28. A blockout device as claimed in claim 27, whereinthe device further comprises one or more device support regions adaptedto be placed upon an upper surface of a masonry block in order tosupport the blockout device relative to the upper surface, and one ormore.
 29. The blockout device as claimed in claim 27, wherein the devicecomprises a plurality of blocking regions and is adapted to block out aplurality of masonry block through cavities.
 30. A blockout device asclaimed in claim 17, wherein at least one said device support regioncomprises the one or more features adapted in use to facilitate securingof at least part of said device support region by a material applied tosaid support region to secure the device to a masonry block.